The fastest and easiest way to learn Spanish, from my experience, is to first talk with someone, chat, speak, etc.
Try to meet girls/boys on the net, and have chat, you can talk about anything and share your phantasms and feelings.
On the net, nobody knows u for real.
You can chat with a woman/man and study ,approve your knowledge.
Try the free links I’ll put for u in the source.

You’ll learn to pronounce better and possible get a less gringo accent.

But you won’t learn how to speak it or be able to call yourself a Spanish “Speaker” Its complicated to master, even I haven’t’ mastered it and its my native tongue!

You actually improve by reading and listening to everyday conversations than by songs.

Yes you can. It was one of the ways that I learned Spanish. I’d stay away from Carribean as well (while the music might be better and more fun, you want more long-winded ballads and verses to learn the language and rhythm):

A few suggestions
1. Marco Antonio Solis (Mexican ballads)
2. Juanes (Colombian)
3. Mercedes Sosa (Argentine, folk songs, complex lyrics)
4. Ricardo Arjona (Guatemalan, rock en espanol)
5. Jorge Drexler (Uruguay, very lyrical)
6. Cafe Tacuba (Mexican alt./punk, complex lyrics)
7. Molotov (Mexican punk/rap, Spanglish/Chilango)
8. Jarabe de Palo (Spanish, rock en espanol)

Possibly

It can’t hurt! Try watching movies in Spanish also.

Yes, it will help you, becasue you will learn idioms, etc. but I don’t recommend learning Spanish from Akwid! They don’t really speak proper Spanish, it’s more Mexican/ Chicano slang, which is fine, but many of those things are offensive, so I don’t recommend learning from them. But it will help to attune you ear to Spanish. Also, I don’t recommend reggaeton for the same reason. Many of the guys singing reggaeton have Puerto Rican accent- which is hard for other native speakers to understand at times. They leave out the S of many words, and pronounce the r’s like l’s etc. Plus they speak too fast for you to be able to really benefit. I would recommend listening to Spanish from Spain, Mexico, Central and South America.

Yes, but only if you already know the language pretty well. It will improve your pronunciation and your ability to understand native speakers, but it won’t teach you grammar or anything like that. If you already have a working knowledge of Spanish though, listening to native speakers is a great way to improve–and the faster the music is–the better. Try reggaeton; it’s fast, and there’s a lot of slang which is good to be able to understand.